Multilocular Thymic Cyst in a Patient with Untreated HIV/AIDS: Case Report and Review of the Literature

Background: Multilocular thymic cysts (MTCs) in adults with human immunodeficiency virus (HIV) are rarely reported. Case Presentation: We describe a case of symptomatic MTC in a male with untreated HIV. A presumptive diagnosis was established based on radiographic imaging and biopsy. Pathologic diagnosis and exclusion of malignancy were ultimately confirmed the following thymectomy. In conjunction with starting antiretroviral therapy, the patient recovered well post-operatively with a resolution of his presenting symptoms. Conclusion: Our case report and review of the literature serve to highlight MTCs as an important clinical entity occurring in persons with HIV.

CT-Based Radiomics Nomogram for Differentiation of Anterior Mediastinal Thymic Cyst From Thymic Epithelial Tumor

ObjectivesThis study aimed to distinguish preoperatively anterior mediastinal thymic cysts from thymic epithelial tumors via a computed tomography (CT)-based radiomics nomogram.MethodsThis study analyzed 74 samples of thymic cysts and 116 samples of thymic epithelial tumors as confirmed by pathology examination that were collected from January 2014 to December 2020. Among the patients, 151 cases (scanned at CT 1) were selected as the training cohort, and 39 cases (scanned at CT 2 and 3) served as the validation cohort. Radiomics features were extracted from pre-contrast CT images. Key features were selected by SelectKBest and least absolute shrinkage and selection operator and then used to build a radiomics signature (Rad-score). The radiomics nomogram developed herein via multivariate logistic regression analysis incorporated clinical factors, conventional CT findings, and Rad-score. Its performance in distinguishing the samples of thymic cysts from those of thymic epithelial tumors was assessed via discrimination, calibration curve, and decision curve analysis (DCA).ResultsThe radiomics nomogram, which incorporated 16 radiomics features and 3 conventional CT findings, including lesion edge, lobulation, and CT value, performed better than Rad-score, conventional CT model, and the clinical judgment by radiologists in distinguishing thymic cysts from thymic epithelial tumors. The area under the receiver operating characteristic (ROC) curve of the nomogram was 0.980 [95% confidence interval (CI), 0.963–0.993] in the training cohort and 0.992 (95% CI, 0.969–1.000) in the validation cohort. The calibration curve and the results of DCA indicated that the nomogram has good consistency and valuable clinical utility.ConclusionThe CT-based radiomics nomogram presented herein may serve as an effective and convenient tool for differentiating thymic cysts from thymic epithelial tumors. Thus, it may aid in clinical decision-making.

Excision of rare adult cervical thymic cyst

Cervical thymic cysts (CTCs) represent 1% of all cervical cystic masses. A review of the literature found that CTCs are typically asymptomatic, with a propensity to be left sided. CTCs often require histological evaluation for diagnosis. A 27-year-old male patient presented to an outpatient otolaryngology clinic with worsening bilateral jaw and neck pain and an incidental right-sided neck mass found on cervical MRI. Preoperative differential diagnosis included venolymphatic malformation versus branchial cleft cyst. Histological examination of the excised specimen provided diagnosis of a CTC. Postoperatively, the patient reported improvement in cervical pain. CTCs are a rare cause of lateral neck mass in young adults. Typical presentation included neck enlargement with no symptoms or in some cases compressive symptoms. It is important to consider CTCs when formulating a differential for a lateral neck mass.

A rare case of combined thymoma and a multilocular thymic cyst discovered due to chest pain

Background A thymoma with chest pain and multilocular thymic cysts (MTCs) is very rare. Case presentation A 49-year-old man presented to another hospital complaining of an anterior chest pain. Chest computed tomography (CT) showed an anterior mediastinal tumor 60 × 30 × 55 mm in size. The boundary with the pericardium or left brachiocephalic vein seemed to be partially unclear while enhanced by the contrast medium, and so the tumor could have invaded them. No definitive diagnosis of myasthenia gravis was made although the serum anti-acetylcholine receptor antibody count was high. We performed an extended thymectomy with combined partial resection of left brachiocephalic vein, left upper lobe, and left phrenic nerve. He was discharged with no chest pain and no complications post-surgery. The tumor was pathologically type B2 thymoma with hemorrhage necrosis and MTCs, and we diagnosed Masaoka stage II because of no histological infiltration to the organs. Conclusions We speculated that hemorrhagic necrosis due to infarction in tumor caused the inflammation to spread to the surrounding organs, which was related to the chest pain and the development of MTCs.

A rare case of intrathymic epidermoid cyst

Thymic cysts are a rare abnormality accounting for 1%–3% of all mediastinal masses. In most cases, they are asymptomatic and localized in the anterior mediastinum. Despite their benign nature, the presence of a mass is an indication for surgery to obtain a histological conclusion and reliably exclude an oncological process. Epidermoid cysts are rare and only a few cases are described in the literature. In our case report, we present a rare case of examination and treatment of a patient with a large anterior mediastinum mass, which, according to the results of histology, was an epidermoid cyst of the thymus.

Micronodular Thymoma With Lymphoid Stroma: A Trio of Cases, With Diverse-associated Histological Features

Introduction. Micronodular thymoma with lymphoid stroma (MNTLS) is a rare thymoma subtype characterized by distinctive histological appearance, unique clinical profile, and indolent course with good prognosis. In addition to its distinctive morphology, MNTLS may be associated with diverse histological features, such as thymic cysts and conventional thymoma, complicating the diagnostic picture further. Materials and methods. We report herein an account of 3 elderly patients (male—02; female—01), who presented with anterior mediastinal mass, and underwent robotic thymectomy. Microscopic examination revealed MNTLS in all 3 cases. In addition, 2 cases showed associated histological features in the form of a multilocular thymic cyst and conventional (type B2) thymoma, respectively. All 3 patients are doing well without recurrence or metastasis at 34, 28, and 19 months postsurgery. Conclusions. Awareness of this rare thymoma subtype is vital among pathologists to avoid misdiagnosis and ensure appropriate patient management. To date, only a few cases of this rare thymoma subtype have been reported in the literature, mostly as single case reports.

Diagnostic value of echocardiography in paracardiac cystic lesions: 43 cases from one single medical center

Paracardial cystic lesions (PCLs) are rare, benign lesions and may occur in any part surrounding the heart. It covers a variety of pathological types, including pericardial cysts, thymic cysts, bronchogenic cysts and so on. The aim of this study was to summarize the diagnostic value of echocardiography in different pathological types of the PCLs. Echocardiographic features of 43 consecutive PCL patients treated at the Union Hospital from January 2002 to December 2017 were compared and analyzed with their surgical and pathological findings retrospectively. The PCLs included 19 pericardial cysts, 12 thymic cysts, 7 bronchogenic cysts, 3 cystic teratomas, 1 enteric cyst and 1 lymphangioma. Among them, 29 cases (67.4%) were accurately diagnosed by echocardiography and 14 cases (32.6%) were missed the diagnosis. All diagnosed cysts were showed as thin-walled, monolocular, echo-free structures without blood flow signals in echocardiographic images. 4 patients had compression of the heart and great vessels caused by cysts. In addition, 4 intracardiac lesions were diagnosed by echocardiography and the results were further confirmed in surgery. Echocardiography is of great value in the diagnosis of paracardiac cystic lesions as well as combined intracardiac lesions. Differential diagnosis could be mainly made based on the location of the lesions.